The Small Spec Bearing is a high quality Size A (5x10x4 mm) stainless steel bearing yo-yo for small bearing compatible yo-yos.

The Large Spec Bearing is a Size C (.250 x .500 x .187) and fits the majority of all YoYoFactory brand yo-yos.

The SPEC is a newer bearing designed to be a more versatile, durable bearing not as focused on flat out performance of the SPEC and CENTER TRAC. It comes without shields for easy access to the race for cleaning and lubrication, and is built tighter and more robust for an extended bearing life. It has a very short break-in period, tends to make less noise and is less prone to failure or lockups due to impact or lack of lubrication.

The SPEC XS is a small bearing that fits the Loop 900, Loop 1080, and Mighty Flea.

Generally speaking all Bearings do go through phases of break-in where the noise of the bearing will change over its life. Bearings do need to be maintained and are designed to operate with some lubrication. While they can be run dry performance may be compromised in the long run.